While you are in UEFI settings screen, give boot priority to “Legacy Support” and “Legacy First“

Change boot order. Move “DVD-ROM” to up (as it was in the old days…)

Legacy Support and Boot Order

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Finally, you will be able to boot from whatever media you want.

Solution for the second challenge:Change the partition table from GPT to MBRNormally, you can change the partition table in Disk Management in Windows. In this case, you can’t do it because there will be only one disk and you cannot change the partition type of the disk your OS is installed in it. Instead, follow these steps:

Download a “live CD” such as Ubuntu, Knoppix, Ophcrack which will give you the opportunity of having an operating system without formatting the disk.

Burn the ISO file to CD and boot your computer from it

Open Disk Management Utility of the system you use. For example, it is called “Disk Utility” in Ubuntu or “GParted Partition Editor” in Ophcrack.

Change the partition type as MBR or msdos (Name might be different depending on the management software)